Sen. Jeff Sessions (R-Ala.) has enlisted the aid of an anti-free-trade group in his quixotic campaign to provide protections for an Alabama sleeping bag maker as part of a looming trade bill.

In an eleventh-hour bid to add an earmark to the Generalized System of Preferences measure, Sessions has called in the American Manufacturing Trade Action Coalition — despite the fact that he has long been a supporter of free-trade deals that AMTAC has vehemently opposed.

Although Democratic and GOP aides said it appears unlikely Sessions will prevail, his maneuverings have caused heartburn for both Democratic and Republican leaders. The GSP bill has now become the linchpin to a deal leaders made with President Barack Obama to pass a trade assistance bill and three key trade agreements that have languished for years. Any changes to the GSP could endanger its passage and bring down the broader agreement.

With the Senate set to hold a key procedural vote on the GSP bill this evening, Sessions has set up a private briefing for Senate staffers with AMTAC Executive Director Auggie Tantillo that "will focus on the renewal of GSP and its implications for the sleeping bag textile industry and domestic jobs," according to an email invite sent to lawmakers' trade legislative aides.

The GSP bill governs how the U.S. treats imports from "least developed countries" such as Indonesia, Thailand, Uruguay and Bangladesh, and it is designed to help bolster trade with the most impoverished parts of the world.

Although the bill has been routinely reauthorized for years, it lapsed last year after Sessions blocked the measure because of language that allows for the import of cheap Bangladeshi sleeping bags.

That language, Sessions contends, has hurt Alabama-based sleeping bag maker Exxel Outdoors. Last year, despite pressure from his colleagues, the Senator refused to lift a hold on the bill unless an exception for Exxel Outdoors was added.

Imports of products covered under the law have dropped sharply since then, and supporters said tens of thousands of U.S. jobs are at stake if Congress does not quickly extend the law. Given the emphasis that voters have put on jobs over the past two years, Sessions' intransigence has rubbed some of his colleagues the wrong way.

Further complicating his efforts is the fact that the provision he wishes to include in the bill is defined under House rules — as well as the Senate GOP's internal rules — as an earmark. House rules explicitly bar consideration of legislation including earmarks — even those intended to close loopholes in current law.

Sessions has found himself increasingly isolated over the past six months, especially after leadership in both chambers cut a deal with the White House to attach the GSP to the Trade Adjustment Assistance reauthorization, which helps workers who have been adversely affected by international trade.

But Sessions has remained undeterred. Although his office refused to comment for this story, aides familiar with the situation said Sessions has continued to block a unanimous consent agreement to move the GSP — forcing the cloture vote.

With few allies in the House or Senate, Sessions has apparently turned to AMTAC in the waning days of the debate.

Tantillo said that while AMTAC is not opposed to international trade per se, he acknowledged that the group — and the companies it represents — has been opposed to much of the nation's trade policy "of the last 30 years."

Tantillo, who said AMTAC does not "necessarily oppose renewal of GSP," said his organization's primary concern has been with the South Korean trade pact.

"We were not pleased at all with the terms of the Korea agreement" that were negotiated by the Bush administration, Tantillo said, adding that AMTAC "did not believe" the Obama administration should have moved forward with the agreement.

While Tantillo said "there have been times in the past he's supported things we were interested in," a comparison of Sessions' voting record and AMTAC's key votes shows little in common.

Since Sessions was elected in 1997, AMTAC has key-voted five trade bills: fast-track authority for the president in 2002, the Chile and Singapore trade agreements in 2003, permanent most-favored-nation status for China in 2000, the Morocco free-trade deal in 2004 and a Central American free-trade agreement in 2005.

But Sessions only voted against the Moroccan trade deal and the fast-track authority bills. The Senator has voted for numerous other trade agreements that were not designated as key votes by AMTAC, including deals with Oman and Peru, as well as an amendment in 2009 to eliminate "Buy American" provisions of existing law.

A number of Senate aides on both sides of the aisle also noted that Sessions has not raised objections to the South Korean trade deal — nor any of the other agreements tied to the passage of the GSP this week.

Sessions' alliance with the organization has raised eyebrows among Republicans.

"It can't be comfortable to lobby Republican colleagues for an earmark in a trade bill with a protectionist group dedicated to killing free trade. It'll be about as effective as using the Teamsters to persuade the tea party to increase funding for the National Labor Relations Board," a former GOP leadership aide familiar with the situation said Friday.